Method and system for a traffic management network

ABSTRACT

A system for collecting traffic data includes at least one first node, at least one second node, and a central processing station. The first node includes a cellular communications module and a first networking communications module connected to a first processor. The second node includes a second networking communications module and a device detection module connected to a second processor. The at least one first node and the at least one second node form a network. The device detection module detects devices associated with traffic. The central processing station can be linked to the at least one first node via the cellular communications module. The at least one second node communicates information associated with the devices associated with traffic to the at least one first node. The at least one first node communicates the information associated with the devices associated with traffic to the cellular communications module.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application claims priority from Provisional Application U.S.Application 61/211,702, filed Apr. 2, 2009, incorporated herein byreference in its entirety.

BACKGROUND

The field of the disclosure relates generally to traffic managementsystems. More specifically, the disclosure relates to a trafficmanagement system that collects information using a network.

Currently, various types of information service providers (ISPs) providetraffic information to users. The various types of ISPs include trafficand map systems such as Westwood One, Traffic.com/Navteq, Clear ChannelTraffic; portal systems such as Yahoo!, Google, MapQuest/AOL, MicroSoftMSN; wireless carriers such as Verizon Wireless, Cingular Wireless,Sprint Nextel, T-Mobile; telematics and navigation systems—GM OnStar,Ford, Toyota, XM Satellite Radio, Sirius Satellite Radio, Garmin,TomTom, Magellen, Motorola, AAA; and media companies such as NBC, ABC,CBS, etc. With the improvement in the quality and the granularity oftraffic and travel time information, ISPs attempt to provideroute-specific travel time information and dynamic route guidanceinformation to individual users to influence the individual's travelchoices including departure time, arrival time, route, destination, etc.An individual traveler relies on the ISP's information and personalexperiences and preferences to make individual decisions for theirtravel choices.

As ISPs provide route-specific travel time information and dynamic routeguidance information to more and more individual users, marketpenetration of actionable traffic information services may increaserapidly. As this type of actionable traffic information provision marketpenetration reaches a critical threshold, users with similar traffic andtravel time information may compete for the shortest travel time routescreating new congestion for these routes. For example, users in the SanFrancisco Bay Area typically choose US 101 to travel from San Franciscoto San Jose. When severe congestion occurs on US 101, for example, dueto a major traffic accident, many ISPs advise motorists to use alternateroutes I-280 or El Camino Real to avoid major congestion on US 101.However, with the diversion of a large number of users from US 101 toI-280 or El Camino Real these routes quickly become congested.

In order to populate these systems, large amounts of traffic data needto be collected. The traffic and travel time information can also beused for traffic studies, for monitoring traffic flow, or for detectingaccidents. However, it is expensive to collect the traffic information.Traffic information is typically collected by closed-circuit videocameras, observers or by axle counters. Video cameras can be used byemployees to determine general traffic flow and detect problems likeaccidents. However, closed-circuit video systems are expensive tomaintain and operate. Observer based studies are comprehensive butexpensive to conduct over long periods. Axle counters can be deployedfor long periods, but the counters must be collected for processing,Moreover, using current detection methods, travel times are inferredfrom speed detections which themselves are often derived from vehiclecounts, yielding errors of up to 35-40%. Thus, improved systems andmethods for collecting traffic data are needed.

SUMMARY

A representative embodiment relates to a system for collecting vehiculartraffic data. The system for collecting vehicular traffic data includesat least one first node, at least one second node, and a centralprocessing station. The first node includes a cellular communicationsmodule and a first networking communications module connected to a firstprocessor. The second node includes a second networking communicationsmodule and a device detection module connected to a second processor.The at least one first node and the at least one second node form anetwork. The device detection module detects devices associated withvehicular traffic. The central processing station can be linked to theat least one first node via the cellular communications module. The atleast one second node communicates information associated with thedevices associated with traffic to the at least one first node. The atleast one first node communicates the information associated with thedevices associated with traffic to the cellular communications module.

Another representative embodiment relates to an apparatus for collectingtraffic data. The apparatus includes a cellular communications module, anetworking communications module, and a device detection moduleconnected to a processor. The device detection module detects devicesassociated with traffic. The networking communications modulecommunicates information associated with the devices associated withtraffic to a central processing station.

BRIEF DESCRIPTION

FIG. 1 is a diagram of a traffic data collection node in accordance witha representative embodiment.

FIG. 2 is a diagram of a simplified traffic data collection node inaccordance with a representative embodiment.

FIG. 3 is a functional diagram of the traffic data collection node ofFIG. 1 in accordance with a representative embodiment.

FIG. 4 is a diagram of an overview of a traffic data collection nodearchitecture in accordance with a representative embodiment.

FIG. 5 is a flowchart of operations performed by a MAC address detectorin accordance with a representative embodiment.

FIG. 6 is a diagram of a MAC address detection packet in accordance witha representative embodiment.

FIG. 7 is a diagram of a cellular packet-based network in accordancewith a representative embodiment.

FIG. 8 is a diagram of a clustered tree type mesh-cellular packet-basednetwork in accordance with a representative embodiment.

FIG. 9 is a diagram of a daisy-chain type mesh-cellular packet-basednetwork in accordance with a representative embodiment.

FIG. 10 is a diagram of a traffic management system in accordance with arepresentative embodiment.

FIG. 11 is an illustration of a traffic map in accordance with arepresentative embodiment.

DETAILED DESCRIPTION

A method, system, and apparatus for a traffic management network aredescribed. In the following description, for purposes of explanation,numerous specific details are set forth to provide a thoroughunderstanding of representative embodiments of the invention. It will beevident, however, to one skilled in the art that the invention may bepracticed without these specific details. The drawings are not to scale.In other instances, well-known structures and devices are shown insimplified form to facilitate description of the exemplary embodiments.

Traffic Data Collection Node

Referring to FIG. 1, a diagram of a traffic data collection node 100 inaccordance with a representative embodiment is shown. The traffic datacollection node 100 includes a computing module 110, an energy storagedevice 130, an energy controller 135, a solar panel 140, a Bluetoothantenna 150, a cellular antenna 160, and a network antenna 165. Thetraffic data collection node 100 can also optionally include a camera170, a microphone 180, and a sensor 190. The computing module 110,energy storage device 130, and energy controller 130 are contained in aprotective enclosure 120.

The protective enclosure 120 can be a weatherproof fiberglass enclosure,for instance, a NEMA-4 rated enclosure. Other materials such as steel,plastic, or carbon fiber can be used. Some or all of the components,including the antennas, can be enclosed in the protective enclosure 120.The protective enclosure 120 can also include a mount for attaching thetraffic data collection node 100 to telephone poles, road signs,barriers, etc.

In at least one embodiment, the traffic data collection node 100 can beabout the size of a brick, or smaller. The traffic data collection node100 can be deployed temporarily or permanently. The traffic datacollection node 100 should be placed within radio frequency (RF)proximity of the travel stream of the devices to be detected. Hence, thetraffic data collection node 100 can be attached to any existingstructure, pole, or strut. The traffic data collection node 100 can beplaced directly on the ground, behind guardrails, or mounted to a post.Placement of the traffic data collection node 100 is limited only bypractical concerns of safety and security of roadside equipment.

The computing module 110 can be a printed circuit board includingprocessors, memory, input/output modules, hard disk drives, solid statedrives, flash memory, transmitters, receivers, controllers, integratedantennas, and slots. The slots can be used to add upgrade modules orother features such as detectors, machine vision processors, andspeakers. The computing module 110 can have varying degrees ofintegration.

Energy storage device 130 and solar panel 140 provide power to thetraffic data collection node 100. Energy controller 135 controlsrecharging of the energy storage device 130 by solar panel 140; andregulates power to the computing module 110 and other components of thetraffic data collection node 100. The energy storage device 130 can be abattery, for example a 12V, 20-30 aH lithium ion battery. However, theenergy storage device 130 can also be a capacitor, fuel cell, or otherenergy storage device. Alternatively, power can be provided by ahardwired connection. The solar panel 140 can be of various types andwattages, for example a 5 W or 10 W array.

The optional camera 170 can be color, black and white, or infra-red. Thecamera can be used, for example, to take a snapshot or video of traffic.The optional camera 170 can also include machine vision capabilitiessuch the ability to identify and/or count objects. For example, thecamera 170 could be used to identify license plates, a particularlicense plate, or a particular person. The optional camera 170 can alsobe programmed to detect traffic jams and accidents. Likewise, themicrophone 180 can be used to detect traffic volume, noise pollutionlevels, or noise level offenders.

The sensor 190 can be a light sensor, inductance sensor, temperaturesensor, a global positioning system (GPS) module, biological/nuclearmaterials sensor or any other kind of sensor. The sensor 190 can also bemore than one or an array of sensors. The sensor 190 can be part of alarger grid of sensors used to monitor weather, temperatures in a city,carbon monoxide levels, detect the threat of a biological materialsrelease, or to detect or monitor the transport of other hazardousmaterials.

The Bluetooth antenna 150, cellular antenna 160, and network antenna 165are antennas designed to transmit and receive signals for theircorresponding technologies. The cellular antenna 160 can be adapted tocommunicate with any cellular network. The network antenna 165 is usedto connect the traffic data collection node 100 to a network of trafficdata collection nodes. For example, the network antenna 165 can becoupled to a ZigBee-type (IEEE 802.15.4) communications module. However,multiple antennas, other antennas, or other communications schemes canbe employed. For example, a satellite transmitter or receiver could beincluded. Additionally, a wired network or communications link can beincluded, such as an Ethernet connection.

The traffic data collection node 100 can also include hardware (e.g.,Bluetooth antenna 150 and network antenna 165) and software configuredto connect the traffic data collection node 100 to various networks suchas a mobile ad hoc network, a vehicular ad hoc network, an intelligentvehicular ad hoc network, or an internet-based mobile ad-hoc network. Amobile ad hoc network (MANET), sometimes called a mobile mesh network,can be a self-configuring network of mobile devices connected bywireless links. A vehicular ad hoc network (VANETs) can be used forcommunication among vehicles and between vehicles and roadsideequipment. An intelligent vehicular ad hoc network (InVANETs) includesartificial intelligence that helps vehicles to behave in intelligentmanners during vehicle-to-vehicle collisions, accidents, drunken drivingetc. Internet-based mobile ad hoc networks (iMANET) are MANETs thatconfigure themselves over internet connections, for example, using acellular network (e.g. using cellular antenna 160) internet connection.Thus, the traffic data collection node 100 can be part of variousnetwork configurations. In one illustrative embodiment, the traffic datacollection node 100 can collect information about other nodes, devices,vehicles, etc. that are networked with the traffic data collection node100. Alternatively, nodes of the traffic management network can beconnected by a hard line such as an Ethernet cable.

The traffic data collection node 100 can include an embedded systemarchitecture including custom embedded hardware design coupled withfirmware. The traffic data collection node 100 detects Bluetooth devicesvia the Bluetooth antenna 150 (for example, ver 2.1/2.0/1.2/1.1 andclass1/2) of vehicles and pedestrians to provide real-time traffic flowto a central processing center. The traffic data collection node 100anonymously discovers Bluetooth Media Access Control (MAC) addresses,which serve as a unique identifier to a Bluetooth device.

A MAC address is a unique identifier assigned to a network adapter byits manufacturer for identification. MAC addresses are anonymousidentifiers. MAC addresses are not associated with any specific useraccount (as is the case with cell phone probes) or any specific vehicle(as with automated toll tags). The MAC address is not linked to aspecific person through any type of central database but is assigned atthe Bluetooth electronic chip manufacturer. Additionally, it isdifficult to match a MAC address to the purchase of a device by aconsumer. The traffic management network, thus minimizes, if noteliminates privacy concerns. In general, users concerned with privacycan set options in their Bluetooth device (often under “Discovery Mode”or ‘Visibility’) to ensure that the device will not be detectable.

After discovering a MAC address, the traffic data collection node 100places an associated time stamp on the discovered Bluetooth MACaddresses and stores the MAC addresses with time stamps in non-volatilememory. The data can then be sent to a central processing center using apacket-based cellular modem via the cellular antenna 160. The data canalso be passed through a wireless mesh based network via the networkantenna 165, where a central node collects data from a mesh network oftraffic data collection nodes. A central traffic data collection nodecan then pass the data to a central processing center.

In addition, the traffic data collection node 100 can detect a signalstrength of a signal associated with the MAC address. The traffic datacollection node 100 can use multiple signal strength measurements todetermine the speed and direction of the device associated with the MACaddress. Alternatively, the traffic data collection node 100 can collectsignal strength data and send it to another device for furtherprocessing.

In order to reduce costs and power usage, various implementations of thetraffic data collection node are possible. For example, some trafficdata collection nodes only require basic features. For example, endpointnode devices could potentially become very simple devices that containonly a Bluetooth radio and a ZigBee radio. The 8-bit microcontroller(used to house the ZigBee stack) that is built into the ZigBee radio canbe used as a controller thereby replacing the ARM7 microcontroller in astandard traffic data collection node. A simplified traffic datacollection node can utilize a smaller solar panel and battery subsystem.Alternatively, the simplified traffic data collection node could relysolely on solar power. Advantageously, the size and cost of a trafficdata collection node can be reduced. The simplified traffic datacollection node can also serve as temporary, portable, low cost node.

Referring to FIG. 2, a diagram of a simplified traffic data collectionnode 200 in accordance with a representative embodiment is shown. Thesimplified traffic data collection node 200 can be, for instance, usedas an end-node in a traffic data collection network. The simplifiedtraffic data collection node 200 includes a microcontroller 210, areal-time clock 212, a memory card 216, an energy storage device 130, aBluetooth module 255, a Bluetooth antenna 150, a network module 262, anda network antenna 165. The simplified traffic data collection node 200can also optionally include a sensor 190. The microcontroller 210,real-time clock 212, memory card 216, energy storage device 130,Bluetooth module 255, Bluetooth antenna 150, network module 262, andnetwork antenna 165 are contained in a protective enclosure 120.

The microcontroller 210, real-time clock 212, memory card 216, energystorage device 130, Bluetooth module 255, Bluetooth antenna 150, networkmodule 262, and network antenna 165 can be integrated onto a singleprinted circuit board including processors, memory, flash memory,transmitters, receivers, controllers, integrated antennas, and slots.The slots can be used to add upgrade modules or other features such asdetectors, machine vision processors, and speakers. The simplifiedtraffic data collection node 200 can have varying degrees ofintegration. For example, the microcontroller 210 and network module 262can be integrated into the same integrated circuit.

The energy storage device 130 can be a battery, for example a 12V, 20-30aH lithium ion battery. The energy storage device 130 can also include apower supply controller that divides the voltage, for example to 1.8 Vand 3.3 V. The simplified traffic data collection node 200 is a lowpower implementation that can operate using the same battery for about10 years.

Other features, as discussed above, can be selectively included. Forexample, sensor 190 can include a camera, a microphone, a globalpositioning system (GPS) module, a specialized sensor or detector.Likewise, the simplified traffic data collection node 200 can betailored for a particular implementation of a network.

Referring now to FIG. 3, a functional diagram of the traffic datacollection node 100 of FIG. 1 in accordance with a representativeembodiment is shown. A computing module 110 of the traffic datacollection node 100 includes a microcontroller 310, configuration/userinterfaces 320, monitoring interfaces 330, a power supply interface 340,and data communication and transport interfaces 350. As discussed above,the computing module 110 can have various levels of integration.

In this example, an energy storage device 130 is integrated onto theprinted circuit board of the computing module 110. The energy storagedevice 130 is a 6 V DC or 12 V DC battery. The energy storage device 130provides power to the power supply interface 340. The power supplyinterface 340 can be, for example, a switching power supply thatconverts the voltage of the energy storage device 130 to lower voltagesfor the components of the computing module 110. For example, the powersupply interface 340 can produce a 1.8 V and 3.3 V source to supply theboard.

The microcontroller 310 is a processor that controls the traffic datacollection node 100. The microcontroller 310 includes acomputer-readable medium such as memory 317 that containscomputer-readable instructions for operating the traffic data collectionnode 100. Microcontroller 310 executes the instructions for operatingthe traffic data collection node 100. Alternatively, memory 317 can bedistinct from microcontroller 310. The microcontroller 310 is clocked bycrystal 315. The microcontroller 310 is also connected to an expansionslot 319. The expansion slot(s) 319 can be used to add additionalcapabilities to traffic data collection node 100; for example a cameraor auxiliary processing module can be added as discussed above.

The microcontroller 310 can be, for example, an ARM7 microcontrollersuch as the ARM7TDMI available from various manufacturers includingTaiwan Semiconductor Manufacturing Company in Hsinchu, Taiwan. TheARM7TDMI core is a 32-bit embedded RISC processor delivered as a hardmacrocell that provides an acceptable combination of performance, powerand area characteristics. The ARM7TDMI core enables system designers tobuild embedded devices requiring small size, low power and highperformance.

The ARM7TDMI core contains 128 kB of internal flash memory for firmwarestorage and 34 kB of internal SRAM for runtime storage. The onboardmemory reduces the need for any external discrete memory subsystems thattraditional Bluetooth based systems require. The microcontroller 310interfaces with three subsystems: configuration/user interfaces 320,monitoring interfaces 330, and data communication and transportinterfaces 350.

The configuration/user interfaces 320 include an input/output interface322, a flash card interface 324, a universal serial bus 326, and aserial port 328. The input/output interface 322 can be any kind ofcommunications port. For example, the input/output interface 322 can bea digital output for triggering a camera, a graphics interface, adigital or analog input coupled to a sensor, or an interface to anauxiliary input/output module.

The flash card interface 324 includes a flash card such as aMicroSD-type flash card. The flash card interface 324 controlscommunications between the microcontroller 310 and a flash card. Theflash card interface 324 can be used for storing data such as discoveredBluetooth MAC addresses or instructions for operating the traffic datacollection node 100. For example, a MicroSD flash can be used to store aBluetooth MAC address data and time stamp that can be retrieved laterfor further processing. A user can retrieve data from the traffic datacollection node 100 by removing and reading the flash card. Similarly, auser can update computer-readable instructions for operating the trafficdata collection node 100 by replacing or updating the flash card.

The universal serial bus 326 and the serial port 328 can also be used tocommunicate with the microcontroller 310. The serial port 328 can be,for instance, a RS-232 or RS-485 type port. The traffic data collectionnode 100 can be configured and serviced via universal serial bus 326and/or the serial port 328. The universal serial bus 326 and the serialport 328 can also be used to attach peripheral devices and sensors suchas cameras, temperature sensors, etc. as discussed above.

The monitoring interfaces 330 include a real-time clock 332, atemperature monitor 336, and an energy source monitor 338. The real-timeclock 332 includes a crystal 331 and a backup battery 335. The crystal331 is, for example, an independent local 32.768 khz crystal oscillator.The backup battery 335 is, for example, a 3.3v lithium ion battery thatprovides power to the real-time clock 332 in the event that main powerhas been lost or the traffic data collection node 100 requiresservicing. Data, time and date stamps produced by the microcontroller310 are maintained via the real-time clock 332, which is clocked fromthe crystal 331 to reduce any potential clock integrity problems.Firmware also provides the ability to synchronize the time and date ofthe real-time clock 332 with a remote network time-date server. As aresult, time and date accuracy is maintained to insure accurate speedcalculation.

The temperature monitor 336 monitors the internal temperature of thetraffic data collection node 100. The temperature monitor 336 includes atemperature sensor or sensors. Data from the temperature monitor 336 arepassed to the microcontroller 310 using, for example, a serialperipheral interface bus. The temperature data can then be sent to acentral processing center for analysis.

The energy source monitor 338 can be, for example, a battery monitor.The energy source monitor 338 monitors energy storage device 130, forinstance, a battery. The energy source monitor 338 can be implemented asan 8-bit analog to digital converter built into the microcontroller 310.The battery health data can then be sent to a central processing centerfor analysis. Alternatively, where the energy storage device 130 is afuel cell, the energy source monitor 338 can send a low fuel warning tothe central processing center.

The data communication and transport interfaces 350 include a cellularmodem 390, a Bluetooth module 380, a network module 370, and an Ethernetmodule 360. The cellular modem 390 transmits and receives data from themicrocontroller 310 via a cellular antenna 160. The cellular modem 390can be a CDMA/GSM wireless module. The cellular modem 390 enablescommunication between the traffic data collection node 100 and a centralprocessing center. The traffic data collection node 100 can send andreceive data packets to and from the central processing center using acellular phone network; thus, the traffic data collection node 100 doesnot have to be hardwired in order to collect and report data.Alternatively, any computer can communicate with the traffic datacollection node 100 via the packet-based cellular phone network. Thecellular modem 390 can also be used to remotely update thecomputer-readable instructions for operating the traffic data collectionnode 100. For example, an over-the-air protocol can be used to reflashthe software. The cellular antenna 160 can be internal, integrated orexternal. The cellular modem 390 connects to a GPRS/EDGE wide areanetwork thus providing a robust data collection capability. Standardizedcellular components can be used to create low-power and low-maintenancedevices.

The Bluetooth module 380 primarily receives but can also transmit datafrom the microcontroller 310 via a Bluetooth antenna 150. The Bluetoothmodule 380 can be, for example, a BlueTooth Class 1 and/or Class 2module, BlueCore4IC available from CSR, plc. of Cambridge, England. TheBluetooth module 380 contains a 2.4 GHz Bluetooth radio, a Bluetoothbaseband digital signal processor (DSP), and a Bluetooth firmware basedstack implemented in an 8-bit microcontroller. The microcontroller 310interfaces to Bluetooth module 380 via a serial universal asynchronousreceiver/transmitter (UART) interface. The Bluetooth module 380 has theability to perform Bluetooth device inquiries. The microcontroller 310can command the Bluetooth module 380 to perform a device inquiry. TheBluetooth module 380 returns the Bluetooth devices discovered inreal-time to the microcontroller 310 to be recorded and logged to theflash card mounted at the flash card interface 324. For example, as acar with a discoverable Bluetooth transponder passes the traffic datacollection node 100, the Bluetooth module 380 can discover the MACaddress of the car's Bluetooth transponder and return the MAC address tothe microcontroller 310. The microcontroller 310 time stamps the MACaddress and saves the data to a flash card mounted at the flash cardinterface 324. Alternatively, other devices can be detected, forexample, the module can be designed to probe for Wi-Fi devices, cellphones, satellite phones, or any other device that transmits a unique orpseudo-unique discovery signal or that responds to wireless inquiries.

The network module 370 transmits and receives data from themicrocontroller 310 via a network antenna 165. The network module 370allows the traffic data collection node 100 to form a network with othertraffic data collection nodes and other simplified traffic datacollection nodes. The network can be, for instance, a mesh network.Alternatively, other network configurations can be used. In one example,the network module 370 is a ZigBee (IEEE 802.15.4) transponder operatingon the 900 MHz Industrial-Scientific-Medical (ISM) band. ZigBee meshnetworking allows for linked data hops between receivers (traffic datacollection nodes). ZigBee is a low-cost, low-power, wireless meshnetworking standard. The low cost allows the technology to be widelydeployed in wireless control and monitoring applications, the lowpower-usage allows longer life with smaller batteries, and the meshnetworking provides high reliability and larger range.

Alternatively, other networking schemes and protocols can be used.Hence, the traffic data collection node 100 can pass data to and fromother the traffic data collection nodes. For example, in a case whereonly a few central nodes are equipped with active cellular modems orhardwired connections, other nodes can pass their data through thenetwork to the central node for upload to a central processing center.Advantageously, the number of nodes requiring an expensive cellularmodem is substantially reduced.

The Ethernet module 360 transmits and receives data from themicrocontroller 310 via a hardline such as a Cat-5 cable. When connectedto an Internet access point, the Ethernet module 360 enablescommunication between the traffic data collection node 100 and a centralprocessing center. Alternatively, any computer can communicate with thetraffic data collection node 100 when the Ethernet module 360 isconnected to an Internet access point. The Ethernet module 360 can alsobe used to update (remotely or onsite) the computer-readableinstructions for operating the traffic data collection node 100.Alternatively, the Ethernet module 360 can be replaced with aweatherproof coaxial-based hardline communications connection; forexample, the traffic data collection node 100 can be connected to acable television network or phone line.

The basic functions of the traffic data collection node can be executedby firmware. Referring to FIG. 4, a diagram of an overview of a trafficdata collection node architecture in accordance with a representativeembodiment is shown. The architecture of the traffic data collectionnode includes a hardware layer 410, a hardware abstraction layer 420, areal-time operating system (RTOS) layer 430 and an application layer440. The hardware layer 410 represents the physical implementation ofthe traffic data collection node as discussed above. The RTOS layer 430consumes about ˜50 kB of flash memory and 32 kB of runtime memory. Ahardware abstraction layer 420 is between the hardware layer 410 and theRTOS layer 430 that allows the real-time operating system to communicatewith the hardware using device drivers.

The application layer 440 includes the following application components:a system health monitor 450, a MAC address logger 460, a MAC addressdetector 470, a configuration interface 480, and a data transportinterface 490. The system health monitor 450 monitors the health of thesystem and signals an alert when the health of the system in danger, forinstance, when the battery is about to die or when the system isoverheating. The MAC address detector 470 interacts with the driver (inthe hardware abstraction layer 420) for the Bluetooth module and detectsthe MAC address of a device, such as a device in a car. The MAC addressdetector 470 notifies the MAC address logger 460 that it transferred anew MAC address element to the MAC address logger 460. The MAC addresslogger 460 records MAC addresses detected along with an associated timestamp. The configuration interface 480 handles the user configurationdialogs that occur over the driver (in the hardware abstraction layer420) that handles the universal serial bus and the serial port. The datatransport interface 490 is responsible for handling the cellular modem,the network module, and the Ethernet module.

Referring to FIG. 5, a flowchart of the operations performed by a MACaddress detector in accordance with a representative embodiment isshown. Additional, fewer or different operations may be performed. In astart operation 510, the MAC address detector initializes and begins theprocess of looking for Bluetooth devices. In a send Bluetooth deviceinquiry command operation 520, the MAC address detector sends an inquirycommand to a Bluetooth module of a traffic data collection node via aBluetooth module device driver which is part of the hardware abstractionlayer. The MAC address detector 470 can look for Bluetooth devicesperiodically or look for Bluetooth devices as soon as resources areavailable. Alternatively, the MAC address detector 470 can change therate it looks for Bluetooth devices based on time of date and priorresults; thus, saving power. The inquiry command orders the Bluetoothmodule to detect any discoverable Bluetooth devices within the range ofthe Bluetooth module's 2.4 GHz radio transceiver, which for class 1devices is about 100 meters and for class 2 devices is about 10 meters.

In a Bluetooth radio interface operation 530, the Bluetooth moduleattempts to find Bluetooth devices. The Bluetooth module, using its ownhardware stack, operates independently of the microcontroller. When theBluetooth module has a result, it interrupts the microcontroller.

In an interrupt service routine operation 540, the real-time operatingsystem services the interrupt and forwards the result to the MAC addressdetector. The interrupt service routine operation 540 is preferably ahigh priority interrupt service routine. If the Bluetooth module did notfind any Bluetooth devices, the MAC address detector returns tooperation 520. However, if a Bluetooth device is found, in a time stampand data log operation 550, the MAC address detector forwards thedetected MAC addresses to the MAC address logger which then appends atime stamp to the detected MAC addresses and saves the data to a flashcard.

Referring to FIG. 6, a diagram of a MAC address detection packet 600 inaccordance with a representative embodiment is shown. The MAC addresslogger assembles the MAC address detection packet 600 and saves the MACaddress detection packet 600 to the flash card. The MAC addressdetection packet 600 includes a traffic data collection node id 610, adetected address 620, a time stamp 630, and a checksum 640. The MACaddress detection packet 600 can be any length, for example, 16 bytes.The traffic data collection node id 610 is the 24 bit MAC address of thetraffic data collection node that detected the Bluetooth device. Thedetected address 620 is the 24 bit MAC address detected by the MACaddress detector. The time stamp 630 is the date, year, and timeassociated with the detection of the detected address 620. The checksum640 is the checksum of the MAC address detection packet 600.

Optionally, the MAC address detection packet 600 can also include otherfields such as data type, extension fields, destination address, andcontrol flags. The MAC address detection packet 600 can be encrypted andinclude features such as forward error correction.

Studies show that about 3-5% of vehicles on U.S. roads have a Bluetoothdevice that is in discoverable mode. Thus, when monitoring a road, atraffic data collection node will probably detect one MAC address perminute on average. Hence, the traffic data collection node accumulatesabout 16 bytes of data per minute, or about 960 bytes per hour, or about23 Kbytes per day. Data from a traffic data collection node can be sentto the central processing center about once every 5 minutes with about a80 byte payload.

Traffic Management Network

In accordance with a representative embodiment, a traffic managementnetwork includes a plurality of traffic data collection nodes. Theplurality of traffic data collection nodes of the traffic managementnetwork monitor and measure vehicular and pedestrian flows by measuringanonymous Bluetooth Media Access Control (MAC) addresses. The pluralityof traffic data collection nodes collect MAC addresses from mobiledevices such as headsets and in-dash sync services in cars. A MACaddress is a unique identifier assigned to a network adapter by itsmanufacturer for identification. The data generated using the trafficmanagement network can be used to calculate high quality, high densitytravel times by sampling a portion of actual travel times from a trafficstream.

In accordance with a representative embodiment, computers at a centralprocessing station of the traffic management network match detected MACaddresses. The matched MAC addresses have respective time stamps. Bymatching MAC addresses from traffic data collection nodes at twodifferent locations, computers at the central processing station candetermine the speed and direction of the device associated with the MACaddress.

In a representative embodiment, the traffic management network can bearranged in two configurations: a cellular packet-based network or amesh-cellular packet-based network. Various combinations of the twoapproaches is possible. Alternatively, other networking configurationscan be employed.

In a cellular packet-based network described with respect to FIG. 7,each traffic data collection node has a packet-based cellular modem (GSMor CDMA) which provides the individual traffic data collection nodeswith Internet protocol (IP) based connectivity over apoint-to-point-protocol (PPP) cellular link. In this configuration, acentral processing center has the capability to communicate with eachtraffic data collection node “directly” over a standard TCP/IP basedcommunication link.

In a mesh-cellular packet-based network described with respect to FIGS.8 and 9, a traffic data collection node can be a coordinator, router, orend-point device. Coordinators collect data packets from other trafficdata collection nodes in the traffic management network. Thecoordinators send the data packets to a central processing server via acellular packet-based modem, which provides the coordinator node withIP-(internet protocol) based connectivity over a point-to-point-protocol(PPP) cellular link. Routers pass along data packets from other trafficdata collection nodes in the traffic management network. End-points onlysend data packets to other traffic data collection nodes.

Referring to FIG. 7, a diagram of a cellular packet-based network 700 inaccordance with a representative embodiment is shown. The cellularpacket-based network 700 monitors, for example, traffic on a road 710.Traffic data collection nodes 732, 734, 736 and 738 are located near theroad 710 so that when a vehicle 720 passes, the traffic data collectionnodes 732, 734, 736 and 738 can detect a discoverable MAC address. Eachof the traffic data collection nodes 732, 734, 736 and 738 is wirelesslyconnected to one of cellular base stations 742, 744 or 746. The cellularbase stations 742, 744 and 746 are connected to Internet 750. A centralprocessing station 770 is also connected to the Internet 750.

The traffic data collection nodes 732, 734, 736 and 738 pass collecteddata to the central processing station 770 using IP packets. Each of thetraffic data collection nodes 732, 734, 736 and 738 is assigned a staticIP address. Alternatively, the nodes can be assigned an IP addressdynamically using Dynamic Host Configuration Protocol (DHCP). When thetraffic data collection nodes 732, 734, 736 and 738 are initialized,they each form a point-to-point-protocol (PPP) cellular link to thecentral processing station 770. Since, each of the traffic datacollection nodes 732, 734, 736 and 738 has its own link to the centralprocessing station 770, the nodes can be placed as far apart as desired.The nodes can periodically or continuously upload data to the centralprocessing station 770.

Each of the nodes communicates to the central processing station 770independently, though the central processing station 770 can coordinatedata collection and other activities amongst the nodes. For example,when the vehicle 720 passes traffic data collection node 732, trafficdata collection node 732 detects the MAC address of vehicle 720. Trafficdata collection node 732 time stamps and stores the data as a MACaddress detection packet. Traffic data collection node 732 then sends anIP packet, addressed to the central processing station 770 andcontaining MAC address detection packet, to the base station 742. The IPpacket may contain many MAC address detection packets. The base station742 routes the IP packet to the Internet 750. The IP packet arrives atthe central processing station 770. The central processing station 770un-encapsulates the IP packet and processes the MAC address detectionpacket.

Likewise, when the vehicle 720 passes traffic data collection node 738,traffic data collection node 738 detects the MAC address of vehicle 720.Traffic data collection node 738 time stamps and stores the data as aMAC address detection packet. Traffic data collection node 738 thensends an IP packet, addressed to the central processing station 770 andcontaining MAC address detection packet, to the base station 746. The IPpacket may contain many MAC address detection packets. The base station746 routes the IP packet to the Internet 750. The IP packet arrives atthe central processing station 770. The central processing station 770un-encapsulates the IP packet and processes the MAC address detectionpacket. Thus, each of the traffic data collection nodes 732, 734, 736and 738 has its own link to the central processing station 770.

The mesh-cellular packet-based network can take various forms, forinstance, a clustered tree type configuration or a daisy-chain typeconfiguration. Advantageously, the mesh-cellular packet-based networkreduces the number of cellular modems needed for communicating with thecentral processing station thereby reducing hardware costs and usagefees. In a city-type environment, the traffic management network can bea clustered tree type configuration including coordinator nodes, routernodes, and endpoint nodes. In a highway-type environment, the trafficmanagement network can be a daisy-chained type configuration includingmostly coordinator nodes and router nodes.

Referring to FIG. 8, a diagram of a clustered tree type mesh-cellularpacket-based network 800 in accordance with a representative embodimentis shown. The traffic data collection nodes of the clustered tree typemesh-cellular packet-based network 800 can be a coordinator node 810, arouter node 820, 822, 824 and 826, or an end-point node 830, 834 and836. All of the nodes can have the ability to detect BlueToothaddresses.

The coordinator node 810 is logically central to the network orsub-network and stores all information about the mesh network. Thecoordinator node 810 can have a communication link, for example, aZigBee-based networking link, to router nodes or end-point nodes. Thecoordinator node 810 can be, for example, a traffic data collection nodeas described above. The coordinator node 810 can preprocess data andperform local analysis on data points. The coordinator node 810 andassociated router nodes or end-point nodes can be spaced about 0.2 to 1mile apart. In FIG. 8, the coordinator node 810 has direct wirelessconnections to four router nodes 822, 826 and 820.

The coordinator node 810 is wirelessly connected to a cellular basestation 840. The cellular base station 840 is connected to Internet 750.A central processing station 770 is also connected to the Internet 750.The coordinator node 810 passes collected data to the central processingstation 770 using IP packets. The coordinator node 810 is assigned astatic IP address. Alternatively, a coordinator node can be assigned anIP address dynamically using DHCP. When the coordinator node 810 isinitialized, it forms a point-to-point-protocol (PPP) cellular link tothe central processing station 770.

The router nodes 820, 822, 824 and 826 serve as intermediate nodes andare responsible for passing data to and from coordinator nodes, otherrouter nodes, and endpoint nodes over a communication link, for example,a ZigBee based networking link. The router nodes 820, 822, 824 and 826can preprocess data and perform local analysis on data points. Somerouter nodes also contain the capability of utilizing a cellularpacket-based modem to alert a central processing server 770 that acoordinator node has failed or is unreachable. The router nodes 820,822, 824 and 826 can be, for example, a traffic data collection node asdescribed above. The router nodes 820, 822, 824 and 826 and associatedrouter nodes or end-point nodes can be spaced about 0.2 to 1 mile apart.

The end-point nodes 830, 834 and 836 can contain just enoughfunctionality to communicate with a single coordinator node or a singlerouter node over a communication link, for example, a ZigBee basednetworking link. The end-point nodes 830, 834 and 836 can be, forexample, a simplified traffic data collection node as described above.The end-point nodes 830, 834 and 836 pass data to the router nodes 820,822, 824 and 826 or the coordinator node 810. The end-point nodes 830,834 and 836 can preprocess data and perform local analysis on datapoints. Because, nodes in a city-environment can be more clustered,cheaper end-point nodes can be used instead of more expensive routernodes. The end-point nodes 830, 834 and 836 provide the ability to placea low-cost, low-powered simplified traffic data collection node in anurban city-type environment to provide high traffic resolution in anarea where roads may be tightly clustered together.

The clustered tree type mesh-cellular packet-based network 800 can beself-forming and self-healing. When the coordinator node 810, the routernodes 820, 822, 824 and 826, and end-point nodes 830, 834 and 836 areactivated, they all attempt to self-form a mesh network by buildinglinks to each other. The end-point nodes 830, 834 and 836 attach to oneof the router nodes 820, 822, 824 and 826, for instance, whicheverrouter node provides the best network connection. The coordinator node810 and the router nodes 820, 822, 824 and 826 attempt to build links toeach other. The clustered tree type mesh-cellular packet-based network800 attempts to reduce the number of active cellular modems in thesystem while still maintaining adequate data bandwidth. Hence, theclustered tree type mesh-cellular packet-based network 800 can have morethan one coordinator node. The clustered tree type mesh-cellularpacket-based network 800 can re-link in order to balance data loads.Additionally, if the links in the clustered tree type mesh-cellularpacket-based network 800 fail or become weak, the clustered tree typemesh-cellular packet-based network 800 self-heals when the nodes formnew links or paths between each other that avoid the failing node orweak link.

The clustered tree type mesh-cellular packet-based network 800 monitors,for example, traffic on a road 710. The coordinator node 810, the routernodes 820, 822, 824 and 826, and the end-point nodes 830, 834 and 836are mostly located near the road 710 so that when a vehicle 720 passes,the coordinator node 810, the router nodes 820, 822, 824 and 826, andthe end-point nodes 830, 834 and 836 can detect a discoverable MACaddress.

When the vehicle 720 passes end-point node 834, the end-point node 834detects the MAC address of vehicle 720. The end-point node 834 timestamps and stores the data as a first MAC address detection packet. Theend-point node 834 sends the MAC address detection packet to router node824; however, the end-point node 834 may only pass data to itsassociated router periodically. Router node 824 sends the first MACaddress detection packet to router node 822. Router node 822 sends thefirst MAC address detection packet to coordinator node 810.

The coordinator node 810 then sends an IP packet, addressed to thecentral processing station 770 and containing the first MAC addressdetection packet, to the base station 840. The IP packet may containmany MAC address detection packets from various router nodes and endpoint nodes. The base station 840 routes the IP packet to the Internet750. The IP packet arrives at the central processing station 770. Thecentral processing station 770 un-encapsulates the IP packet andprocesses the first MAC address detection packet.

Later, when the vehicle 720 passes end-point node 836, the end-pointnode 836 detects the MAC address of vehicle 720. The end-point node 836time stamps and stores the data as a second MAC address detectionpacket. The end-point node 836 sends the second MAC address detectionpacket to router node 826; however, the end-point node 836 may only passdata to its associated router periodically. Router node 826 sends thesecond MAC address detection packet to coordinator node 810.

The coordinator node 810 then sends an IP packet, addressed to thecentral processing station 770 and containing the second MAC addressdetection packet, to the base station 840. The IP packet may containmany MAC address detection packets from various router nodes and endpoint nodes. The base station 840 routes the IP packet to the Internet750. The IP packet arrives at the central processing station 770. Thecentral processing station 770 un-encapsulates the IP packet andprocesses the second MAC address detection packet.

The central processing station 770 can analyze the first MAC addressdetection packet and the second MAC address detection packet. Forexample, the central processing station 770 can use the data to monitoror analyze traffic conditions. In particular, the speed of the vehicle720 can be calculated by knowing the positions of end-point node 834 andend-point node 836 and the time difference of the time stamps recordedthe first MAC address detection packet and the second MAC addressdetection packet. The positions of end-point node 834 and end-point node836 can be determined and recorded at installation, determined by globalpositioning system (GPS) modules included in the nodes, or determinedusing triangulation techniques in combination with the cellular network.

Referring to FIG. 9, a diagram of a daisy-chain type mesh-cellularpacket-based network in accordance with a representative embodiment isshown. The traffic data collection nodes of the daisy-chain typemesh-cellular packet-based network 900 can be a coordinator node 810, arouter node 920, 921, 922, 923, 924, 925, 926, 927 and 929, or anend-point node (not shown). All of the nodes can have the ability todetect BlueTooth addresses.

The coordinator node 810 is logically central to the network orsub-network and stores all information about the mesh network. Thecoordinator node 810 can have a communication link, for example, aZigBee based networking link, to router nodes or end-point nodes. Thecoordinator node 810 can be, for example, a traffic data collection nodeas described above. The coordinator node 810 can preprocess data andperform local analysis on data points. The coordinator node 810 andassociated router nodes or end-point nodes can be spaced about 0.2 to 1mile apart. The coordinator node 810 can be linked to more than onedaisy chain. For example, coordinator node 810 is linked to the daisychain associated with Highway ‘A’ 910 and the daisy chain associatedwith Highway ‘B’ 915.

The coordinator node 810 is wirelessly connected to a cellular basestation 840. The cellular base station 840 is connected to Internet 750.A central processing station 770 is also connected to the Internet 750.The coordinator node 810 passes collected data to the central processingstation 770 using IP packets. The coordinator node 810 is assigned astatic IP address. Alternatively, a coordinator node can be assigned anIP address dynamically using DHCP. When the coordinator node 810 isinitialized, it forms a point-to-point-protocol (PPP) cellular link tothe central processing station 770.

The router nodes 920, 921, 922, 923, 924, 925, 926, 927 and 929 serve asintermediate nodes and are responsible for passing data to and fromcoordinator nodes, other router nodes, and endpoint nodes over acommunication link, for example, a ZigBee based networking link. Therouter nodes 920, 921, 922, 923, 924, 925, 926, 927 and 929 canpreprocess data and perform local analysis on data points. Some routernodes also contain the capability of utilizing a cellular packet-basedmodem to alert a central processing server 770 that a coordinator nodehas failed or is unreachable. The router nodes 920, 921, 922, 923, 924,925, 926, 927 and 929 can be, for example, a traffic data collectionnode as described above. The router nodes 920, 921, 922, 923, 924, 925,926, 927 and 929 and associated router nodes or end-point nodes can bespaced about 0.2 to 1 mile apart.

Some of router nodes act as child router nodes, where the daisy chainlinks to the parent coordinator node. For example, router nodes 924 and929 are child router nodes. Router nodes 924 and 929 are intermediatenodes for the rest of the nodes in the daisy-chained configuration.Router nodes 924 and 929 can also backup the coordinator node 810 iscase of failure by becoming coordinator nodes.

The daisy-chain type mesh-cellular packet-based network 900 isself-forming and self-healing. When the coordinator node 810, and therouter nodes 920, 921, 922, 923, 924, 925, 926, 927 and 929 (and anyend-point nodes) are activated, they all attempt to self-form a meshnetwork by building links to each other. The coordinator node 810 andthe router nodes 920, 921, 922, 923, 924, 925, 926, 927 and 929 attemptto build links to each other. The central processing station 770 canalso direct the nodes to form a specific network configuration based onthe node location, maps, predicted demand, etc. The daisy-chain typemesh-cellular packet-based network 900 attempts to reduce the number ofactive cellular modems in the system while still maintaining adequatedata bandwidth. Hence, the daisy-chain type mesh-cellular packet-basednetwork 900 can have more than one coordinator node. The daisy-chaintype mesh-cellular packet-based network 900 can re-link in order tobalance data loads. Additionally, if the links in the daisy-chain typemesh-cellular packet-based network 900 fail or become weak, thedaisy-chain type mesh-cellular packet-based network 900 self-heals whenthe nodes form new links or paths between each other that avoid thefailing node or weak link.

The daisy-chain type mesh-cellular packet-based network 900 monitors,for example, traffic on Highway ‘A’ 910. The coordinator node 810, therouter nodes 921, 922, 923, 924, 925, 926 and 927 are mostly locatednear Highway ‘A’ 910 so that when a vehicle 720 passes, the coordinatornode 810 and the router nodes 921, 922, 923, 924, 925, 926 and 927 candetect a discoverable MAC address.

When the vehicle 720 passes router node 921, the router node 921 detectsthe MAC address of vehicle 720. The router node 921 time stamps andstores the data as a first MAC address detection packet. The router node921 sends the MAC address detection packet to router node 922; however,the router node 921 may only pass data to its associated routerperiodically. Router node 922 sends the first MAC address detectionpacket to router node 923. Router node 923 sends the first MAC addressdetection packet to router node 924, which is a child router node.Router node 924 sends the first MAC address detection packet tocoordinator node 810.

The coordinator node 810 then sends an IP packet, addressed to thecentral processing station 770 and containing the first MAC addressdetection packet, to the base station 840. The IP packet may containmany MAC address detection packets from various router nodes and endpoint nodes. The base station 840 routes the IP packet to the Internet750. The IP packet arrives at the central processing station 770. Thecentral processing station 770 un-encapsulates the IP packet andprocesses the first MAC address detection packet.

Later, when the vehicle 720 passes router node 927, the router node 927detects the MAC address of vehicle 720. The router node 927 time stampsand stores the data as a second MAC address detection packet. The routernode 927 sends the second MAC address detection packet to router node926; however, the router node 927 may only pass data to its associatedrouter periodically. Router node 926 sends the second MAC addressdetection packet to router node 925. Router node 925 sends the secondMAC address detection packet to router node 924, which is a child routernode. Router node 924 sends the second MAC address detection packet tocoordinator node 810.

The coordinator node 810 then sends an IP packet, addressed to thecentral processing station 770 and containing the second MAC addressdetection packet, to the base station 840. The IP packet may containmany MAC address detection packets from various router nodes and endpoint nodes. The base station 840 routes the IP packet to the Internet750. The IP packet arrives at the central processing station 770. Thecentral processing station 770 un-encapsulates the IP packet andprocesses the second MAC address detection packet.

The central processing station 770 can analyze the first MAC addressdetection packet and the second MAC address detection packet. Forexample, the central processing station 770 can use the data to monitoror analyze traffic conditions. In particular, the speed of the vehicle720 can be calculated by knowing the positions of router node 921 androuter node 927 and the time difference of the time stamps recorded thefirst MAC address detection packet and the second MAC address detectionpacket. The positions of router node 921 and router node 927 can bedetermined and recorded at installation, determined by globalpositioning system (GPS) modules included in the nodes, or determinedusing triangulation techniques in combination with the cellular network.

Advantageously, the traffic management network enables measurement oftravel time and average vehicle speed with increased accuracy. Roadspeed is derived from travel times and accuracy is assured from thevolume of Bluetooth MAC addresses collected. The origins anddestinations (O-Ds) of BlueTooth devices associated with a moving objectcan be accurately measured at a reduced cost and with a larger samplesize than possible using traditional methods. Advantageously, Bluetoothtraffic monitoring is economical than closed-circuit video cameras,observers or axle counters on a cost per data point basis.

Alternatively, the traffic management network can enable the mapping ofinformation on routing decisions. Tracking Bluetooth MAC addresses canidentify trends in how and when drivers select their route options.Computers at the central processing station can use information providedby the traffic management network to track travel times, originationsand destinations for a variety of modes of transportation (vehicles,rail, and pedestrian) on freeways, arterials and sidewalks (since theBluetooth devices are associated with people rather than vehicles).

Traffic Management System

Referring to FIG. 10, a diagram of a traffic management system 1000 inaccordance with a representative embodiment is shown. The trafficmanagement system 1000 can include a network 1015, nodes 1010, acellular base station 1017, Internet 1035, a central processing station1037, and an application server 1060. The nodes 1010 can be locatedalong or near a road 1022. Road 1022 can include, for example, on-ramp1025 and off-ramp 1020. Road 1022 can also include a first signage 1045,a second signage 1047, and a traffic light 1055. The first signage 1045and the second signage 1047 can be a traffic sign, a message board, atraffic signal, or an electronic billboard.

The nodes 1010 anonymously discover, for example, Bluetooth MACaddresses, as described above. When a vehicle 1027 passes one of thenodes 1010, the particular node attempts to collect MAC addresses ofwireless devices in the vehicle 1027. For example, the nodes 1010 cancollect the MAC addresses of cell phone 1040 and navigation device 1042which are in vehicle 1027. The navigation device 1042 can be a globalpositioning satellite (GPS) unit that matches the unit's location to amap. The nodes 1010 can be connected to the network 1015, as describedabove. For example, the network 1015 can be a daisy-chain typemesh-cellular packet-based network, a clustered tree type mesh-cellularpacket-based network, an Ethernet network, or any other network. One ormany of the nodes 1010 can be communicatively coupled to cellular basestation 1017. Alternatively, each node 1010 can be communicativelycoupled to cellular base station 1017. In addition, other devices suchas first signage 1045 can also be connected to network 1015.

As the cell phone 1040 and navigation device 1042 pass nodes 1010, theMAC addresses of the cell phone 1040 and navigation device 1042 cancollected by nodes 1010, be time stamped, and sent to central processingstation 1037 through network 1015, cellular base station 1017 andInternet 1035, as discussed above. In one illustrative embodiment, thecentral processing station 1037 can use the MAC addresses, nodelocations, and time stamps to determine travel time, vehicle speed, andvehicle direction (directionality), as discussed above. Thus, as manyvehicles pass nodes 1010, various conditions of the road can bedetermined such as traffic congestion and traffic speed. For example, ifa crash 1030 occurs on the road 1022, the central processing station1037 can determine that vehicles are not moving if the nodes 1010 do notdetect progression of the cell phone 1040 and navigation device 1042 orthat vehicles are moving too slowly if the time the cell phone 1040 andnavigation device 1042 take to pass successive nodes implies traffic hasslowed.

Information about vehicle travel time, vehicle speed, and vehicledirection can be shared with an application server 1060 over Internet1035. In one illustrative embodiment, the application server 1060 can beoperated by a third party. The application server 1060 can be used toaggregate traffic data, analyze traffic data, and provide enhancedservices based on the traffic data.

For example, the central processing station 1037 can pass vehicle traveltime, vehicle speed, and vehicle direction associated with the crash1030 to application server 1060. Additional information can also beincluded such as an indication that the crash 1030 has occurred. Theapplication server 1060 can provide information to drivers regarding thecrash 1030. For example, the application server 1060 can send a messageto first signage 1045, via network 1015, instructing the first signage1045 to display a message such as “Accident Ahead. Please slow down.”

Alternatively, application server 1060 can reroute traffic. Theapplication server 1060 can send a message to second signage 1047, viaInternet 1035, instructing the second signage 1047 to display a messagesuch as “Accident Ahead. Temporary Detour. Please Exit” which causesdrivers to take off-ramp 1020, thereby decongesting the road 1022. Theapplication server 1060 can also cause other signage to display drivinginstructions to complete a detour route.

Alternatively, the application server 1060 can send an email or textmessage describing the traffic conditions to cell phone 1040.Alternatively, the nodes 1010 can also send information, such as theaccident warning, back to the cell phone 1040 and navigation device 1042via network 1015 (e.g. over the Bluetooth link). For instance, userscould register for a service that allows the nodes 1010 to pair withtheir Bluetooth devices.

Alternatively, application server 1060 can stop traffic from enteringthe road 1022. For example, application server 1060 can send a messageto a Department of Transportation (DOT) traffic management server 1050,via Internet 1035, informing the DOT that an accident has occurred atthe location of crash 1030. The DOT traffic management server 1050 cancontrol traffic light 1055 to prevent more vehicles from entering theon-ramp 1025, thereby decongesting the road 1022. In addition, theapplication server 1060 and the DOT traffic management server 1050 canuse the vehicle travel time, vehicle speed, and vehicle direction todeploy resources such as police, road crews, ambulances, plows, etc.

In another illustrative embodiment, information regarding trafficconditions can be compiled for various end users. For example,application server 1060 can determine current or historical travel timesfor roads. Referring to FIG. 11, an illustration of a traffic map 1110in accordance with a representative embodiment is shown. The traffic map1110 can show a road system 1120 for a city (depicted as “Big City”).The application server can use vehicle travel time, vehicle speed, andvehicle direction in combination with maps and posted speed limits togenerate traffic map 1110. Traffic map 1110 can show the congestion ofroad system 1120. For example, traffic map 1110 can show areas of lightcongestion 1130, medium congestion 1140, and high congestion 1150.Traffic map 1110 can show accident 1160. Information regarding theaccident 1160, such as location, severity, and driver instructions, canbe determined by the application server 1060 or provided by anothersource such as the DOT. In addition, travel times 1170 can be calculatedand displayed.

Optionally, the traffic map 1110 can also display the location ofcertain vehicles. For example, the MAC address of a wireless deviceassociated with a known vehicle 1180 can be stored by the applicationserver 1060. As discussed above, MAC addresses are anonymous. However,if a user chooses to register the MAC address of his device with adatabase, the device (and the associated person or vehicle) can then betracked. When the known vehicle 1180 passes a node 1010, the MAC addressassociated with the known vehicle 1180, node identifier, and a timestamp can be sent to the central processing station 1037 for processingand then to application server 1060. The application server 1060 canmatch the MAC address with an identifier of the known vehicle 1180. Forexample, MAC address “01:23:45:67:89:ab” could be associated with “citysnow plow 19.” Thus, when MAC address “01:23:45:67:89:ab” is detected ata node, the map can display the location of “city snow plow 19.”Advantageously, a city can track its snow plows and manage resources,for instance, a manager can easily determine what roads have been plowedand need to be plowed.

Likewise, any other vehicle can be matched with a particular MACaddress. For example, police cars, ambulances, road crews, fleets oftrucks, and/or employees can be associated with a MAC address and latertracked. In another illustrative embodiment, parents could track thelocation of their children by registering the MAC address of a child'scell phone in a database. When a teenager is out driving, the MACaddress of the child's cell phone will be detected by nodes. Theapplication server 1060 can match the stored MAC address of the child'scell phone with incoming node data. When the application server 1060detects a match, the application server 1060 can report the location ofthe child based on the detection at the node. Similarly, a parent canalso monitor a child's driving speeds and travel habits.

Referring again to FIG. 10, traffic information, such as the trafficmap, can be displayed and/or analyzed on a computer 1070, a smart phone1075, the cell phone 1040, or the navigation device 1042. The trafficinformation can be combined with other sources of information such asweather, news, resource deployment, and personal data (e.g. travelplans). For example, the navigation device 1042 can use the trafficinformation provided by application server 1060 to reroute travel plansentered by the user. In another example, a user can check a websiteincluding the traffic map of FIG. 11 before leaving for work using thecomputer 1070 or smart phone 1075. Advantageously, users of the trafficmanagement system can quickly receive and/or obtain current trafficinformation in order to adapt to changing road conditions.

Alternatively, a traffic management system can also monitor pedestriantraffic. For example, a traffic management system can be used to monitorcongestion in a terminal such as an airport. In addition, a trafficmanagement system can be used to serve individualized advertisementsusing available signage. For example, a vehicle, or groups of vehicles,associated with a MAC address(es) that has not “stopped” for many hoursmay be targeted with a food advertisement sent to a nearby electronicbillboard. Alternatively, when the user of a registered MAC addresspasses a node near an electronic billboard, an application server cansend an individualized advertisement to the billboard for display.Similarly, an individualized advertisement can be sent to a cell phone,navigation device, etc. based on the location of a node that detects theregistered MAC address. Thus, advertisers such as truck stops can sendadvertisements targeted to a profile of a user with a registered MACaddress as the user passes near a specific location. For instance, theadvertisement could be sent as the vehicle approaches the truck stop.

The foregoing description of the exemplary embodiments have beenpresented for purposes of illustration and of description. It is notintended to be exhaustive or to limit the invention to the precise formdisclosed, and modifications and variations are possible in light of theabove teachings or may be acquired from practice of the invention. Forexample, the described representative embodiments focused on BlueToothdetection and ZigBee networking. The present invention, however, is notlimited to detection of BlueTooth devices. Those skilled in the art willrecognize that the device and methods of the present invention may bepracticed using other connectivity detection means. Additionally, thenetworking can be done using other networking methods. Further, althougha highway-type implementation is described, the system and method for atraffic management network can also be used in a city environment,warehouses, ports, terminals, etc. The embodiments were chosen anddescribed in order to explain the principles of the invention and aspractical applications of the invention to enable one skilled in the artto utilize the invention in various embodiments and with variousmodifications as suited to the particular use contemplated. It isintended that the scope of the invention be defined by the claimsappended hereto and their equivalents.

What is claimed is:
 1. A system for collecting traffic data, comprising:at least one stationary coordinator device comprising: cellularcommunications circuitry connected to a first processor; and firstnetworking communications circuitry connected to the first processor; aplurality of stationary traffic data collection devices positioned alongat least a portion of a road, wherein each stationary traffic datacollection device comprises: second networking communications circuitryconnected to a second processor, wherein the at least one stationarycoordinator device and the stationary traffic data collection deviceform a network via the first networking communications circuitry and thesecond networking communications circuitry; device detection circuitryconnected to the second processor configured to detect deviceidentifiers of devices contained within vehicles traveling on the atleast the portion of the road; and wherein the second processor isconfigured to control transmission of the detected device identifiers toone of the at least one stationary coordinator device via the secondnetworking communications circuitry; and a central processing stationlinked to the at least one stationary coordinator device via thecellular communications circuitry, wherein the central processingstation receives a device identifier of a device from two or morestationary traffic data collection devices via one or more of the atleast one stationary coordinator device, wherein the central processingstation comprises: a third processor configured to: calculate a speed ofthe device on the road, a directionality of the device on the road, anda travel time of the device on the road based upon the received deviceidentifiers from the two or more stationary traffic data collectiondevices and a predetermined distance between the two or more stationarytraffic data collection devices.
 2. The system of claim 1, wherein thedevice detection circuitry is BlueTooth device detection circuitry. 3.The system of claim 2, wherein the first and second networkingcommunications circuitry are ZigBee communications circuitry.
 4. Thesystem of claim 1, wherein the device identifier of the device comprisesa media access control address.
 5. The system of claim 1, wherein thecentral processing station receives a time stamp associated with thedevice identifier.
 6. The system of claim 1, further comprising anapplication server configured to determine traffic congestion of theroad based on at least one of the speed of the device on the road, thedirectionality of the device on the road, and the travel time of thedevice on the road.
 7. The system of claim 6, wherein the applicationserver is configured to generate a traffic display indicating at leastone of levels of congestion on the road, speed of traffic on the road,and travel time on the road.
 8. The system of claim 1, furthercomprising an application server configured to: receive a deviceidentifier and a stationary traffic data collection device location;match the device identifier to a user identifier; and associate the useridentifier with the stationary traffic data collection device location.9. The system of claim 8, further comprising a display configured toindicate a location of an object based on the user identifier and thedevice location.
 10. The system of claim 1, wherein a time stamp isassociated with the device identifier.
 11. The system of claim 10,wherein the first networking communications circuitry is furtherconfigured to communicate with one or more of the plurality ofstationary traffic data collection devices to receive signal strengthsassociated with the device contained within the vehicle, wherein thecentral processing station receives the signal strengths associated withthe device, and wherein the third processor is configured to determine aspeed and direction of the device based upon the detected signalstrengths.
 12. The system of claim 1, wherein at least one of theplurality of stationary traffic data collection devices furthercomprises a camera configured to: take a picture of traffic; and count anumber of license plates within the picture of traffic.
 13. The systemof claim 12, wherein the camera is further configured to detect trafficjams.